Sem carregar na tecla Enter, não consigo enviar o formulário.

In Portuguese, sem + infinitive is a very common way to say without doing something.

So:

• sem carregar = without pressing
• sem dizer nada = without saying anything
• sem abrir a janela = without opening the window

In this sentence, Sem carregar na tecla Enter gives the condition under which the action is impossible.

Because the subject is understood to be the same as in the main clause (eu, from consigo), Portuguese can simply use the infinitive carregar.

Yes — carregar has several meanings, and that often confuses learners.

Common meanings include:

• to carry
• to load
• to charge a battery
• in European Portuguese, to press a button/key

So in Portugal, carregar na tecla Enter means to press the Enter key.

This is very natural in European Portuguese. In other varieties, especially Brazilian Portuguese, you may more often hear:

• apertar
• pressionar

But in Portugal, carregar in this context is completely normal.

In European Portuguese, the verb carregar is often used with the preposition em when talking about pressing buttons, keys, switches, etc.

So:

• carregar em algo
• carregar no botão
• carregar na tecla

Here:

• em + a tecla becomes na tecla

So carregar na tecla Enter literally follows the pattern press on the Enter key.

This is one of those verb + preposition combinations that you largely have to learn as a set.

Na is the contraction of:

• em
  • a = na

Because tecla is feminine singular, Portuguese uses a tecla, and with em that becomes na tecla.

Compare:

• no botão = em + o botão
• na tecla = em + a tecla
• nos menus = em + os menus
• nas opções = em + as opções

So na tecla Enter literally means on the Enter key.

Both conseguir and poder can relate to ability, but they are not exactly the same.

• não posso enviar = I cannot / am not allowed to send
• não consigo enviar = I can’t manage to send / I’m unable to send

In this sentence, não consigo enviar o formulário suggests practical inability: the form won’t go through unless Enter is pressed.

So conseguir fits better because it expresses success or ability in practice, not permission.

This is very common in Portuguese.

• consigo is the conjugated verb
• enviar stays in the infinitive

The pattern is:

• conseguir + infinitive = to manage to / to be able to do something

Examples:

• Consigo abrir a porta. = I can manage to open the door.
• Não consigo dormir. = I can’t sleep.
• Consegues ver isso? = Can you see that?

So:

• não consigo enviar = I can’t send

In Portuguese, não normally goes directly before the verb it negates.

So:

• consigo = I can / I manage
• não consigo = I can’t / I don’t manage

That is the standard word order:

• Não consigo enviar o formulário.
• Não quero sair.
• Não sei.

English sometimes uses do not or cannot, but Portuguese usually just puts não before the verb.

Portuguese uses articles very frequently, often more frequently than English.

Here, o formulário suggests a specific form — the one already being discussed or the one on the screen.

So:

• enviar o formulário = send the form
• enviar um formulário = send a form

If the speaker means a particular known form, o formulário is the natural choice.

Yes, it could — but the meaning and tone change slightly.

Portuguese sometimes uses the personal infinitive after prepositions like sem to show who the subject is.

Compare:

• Sem carregar na tecla Enter, não consigo enviar o formulário.
  = more neutral; the subject is understood from consigo (I)

• Sem carregares na tecla Enter, não consegues enviar o formulário.
  = Without pressing the Enter key, you can’t send the form

So the sentence you were given uses the plain infinitive because the subject is already clear from the main clause.

Not fully. In tecla Enter, Enter is basically the name of the key, while the main noun is tecla.

That is why the grammar agrees with tecla, not with Enter:

• a tecla Enter
• na tecla Enter

So the feminine article and preposition contraction come from tecla.

This is similar to expressions like:

• a tecla Esc
• a tecla Shift

The foreign word names the key, but the grammar is carried by tecla.

The first part is an introductory phrase:

• Sem carregar na tecla Enter, ...

In Portuguese, it is very common to separate this kind of fronted adverbial phrase with a comma, especially when it is a bit longer.

The comma helps mark the pause and makes the sentence easier to read.

So this punctuation is natural and standard:

• Sem carregar na tecla Enter, não consigo enviar o formulário.

You may sometimes see short introductory phrases without a comma, but here the comma is very normal.